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Subject: Re: zfs, a directory that used to hold lot of files and listing pause
To: "Eugene M. Zheganin" <emz@norma.perm.ru>, freebsd-stable@FreeBSD.org
References: <4d9269af-ed64-bb73-eb7f-98a3f5ffd5a2@norma.perm.ru>
From: Miroslav Lachman <000.fbsd@quip.cz>
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Date: Thu, 20 Oct 2016 16:03:09 +0200
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Eugene M. Zheganin wrote on 2016/10/20 15:47:
> Hi.
>
> I have FreeBSD 10.2-STABLE r289293 (but I have observed this situation
> on different releases) and a zfs. I also have one directory that used to
> have a lot of (tens of thousands) files. I surely takes a lot of time to
> get a listing of it. But now I have 2 files and a couple of dozens
> directories in it (I sorted files into directories). Surprisingly,
> there's still a lag between "ls" and an output:

[...]

> I've seen this situation before, on other servers, so it's not the first
> time I encounter this. However, it's not 100% reproducible (I mean, if I
> fill the directory with dozens of thousands of files, I will not
> certainly get this lag after the deletion).

What about snapshots? Are there any snapshots on this filesystem?

Or scrub running in the background?

Miroslav Lachman